[RADIOCARBON, VOL. 5, 1963, P. 118-162] NEW ZEALAND NATURAL RADIOCARBON MEASUREMENTS I-V T. L. GRANT-TAYLOR and T. A. RAFTER Science, New Zealand Geological Survey and Institute of Nuclear Zealand Department of Scientific and Industrial Research, Lower Hutt, New This list comprises dating determinations of the New Zealand Radiocarbon Laboratory. in Fergusson All dates listed herein were published previously (NZ-1-78 in Fergusson and Rafter, 1959) ; and Rafter, 1953, 1955, 1957) ; NZ-79-264 NZ-265 in Grant-Taylor and Rafter, 1962. onward by NZ-1-4 were counted by the solid-carbon method and NZ-10 Rafter (1953, gas-counting methods; details of the methods are given in allowance 1955a) and Fergusson and Rafter (1953, 1955). Where possible, secondary stand- has been made for biological fractionation effects by use of by McCallum ards (Rafter, 1953b). The accuracy of the methods is discussed (1955). carbon in The ages reported have a correction of 120 yr for industrial shallow seas. material that lived on land and of 100 yr in material that lived in has been ex- Material from deep oceanic environments and from Antarctica (Fergusson cluded from this list, even though it may have appeared previously the deep oceans and Rafter, 1957, 1959). It has become clear that material in C14 "dates" on such is formed with a content that varies considerably, and significance material have an initial uncertainty that may exceed 3000 yr. The age. that can be attached to such dates is no more than an upper limit of in In the list, grid references are given for most New Zealand localities The age terms of the National 1000-yd grids published in NZMS-1 maps. old half life of C14In all cases is given in years before A.D. 1950, in terms of the of 5568 ± 30 yr. New We have adhered as closely as possible to the data in the published Zealand lists 1 through 3. Some descriptions have been expanded. dates In conformity with the decision of the Cambridge conference 1963 reassessment in terms of the present calendar are included. However a recent C14 from this source. of the half life of suggests the presence of a 5% error Willis et al., 1960 Also work done by various laboratories, de Vries, 1958, and un- and Jansen, 1962 suggests an additional variation of irregular nature three of the known origin. The magnitude of this variation as determined by of the four laboratories appears to be similar, although the absolute amount by variation at a given time may vary. The maximum deviation as determined C14 tree ring counts is ca. 50% of the age. SAMPLE DESCRIPTIONS Taupo series Dates a violent rhyolitic eruption in NW of Lake Taupo. 118 T. L. Grant-Taylor and T. A. Rafter 119 1820 ± 150 NZ-1. Taupo, N. Z. A.D. 130 Charcoal from coarse Taupo pumice, close to the main Taupo-Rotorua 176° Road ca. 0.5 mi S of burnt Forest Products Plantations (38° 36' S Lat, Soil Bur., 09' E Long), grid ref. N94/624492. Coll. by I. L. Baumgart, N. Z. Wellington. Comment: dates the eruption of pumice blocks that carbonized the wood. 3440 ± 70 NZ-2. Taupo, N. Z. 1490 B.C. Charcoal from fossil soil, in quarry face, ca. 1 mi SE of Terrace Hotel on the Napier Taupo Rd. (38° 43' S Lat, 176° 07' E Long). Coll, by I. L. Baum- gart. Comment: date places a younger limit on underlying Waimahia lapilli member. 1640 ± 70 NZ-3. Taupo, N. Z. A.D. 310 Charcoal from surface of carbonized log in coarse Taupo pumice, depth 3 ft below top of pumice, N. Z. Electricity Dept. road 1/3 mi N of Wanganui River (39° 01' S Lat,175° 37' E Long). Coll. by N. H. Taylor, N. Z. Soil Bur. 1920 ± 150 NZ-4. Taupo, N. Z. A.D. 30 Charcoal from water-sorted Taupo pumice near Desert Rd., S bank of Waihohonu Stream, 18 mi N of Waiouru (39° 13' S Lat, 175° 44' E Long), N112/223734. Coll. by N. H. Taylor. 3170 ± 200 kiriki NZ-5. Rangitawa' Stream near I a 1220 B.C. Wood from Ohakeo alluvium, ca. 1 ft above base of alluvium, which rests unconformably on Castlecliffian sandy mudstone, on S bank of Rangitawa Stream across railway from McLennan's gate (40° 08' S Lat, 175° 27' E Long), N143/953626. Coll. by M. T. Te Punge, N. Z. Geol. Surv., Wellington. Comment: sample dates the alluvium, interpreted as younger postglacial valley fill. NZ-6. Pollen Island, Waitemata Harbor >31,000 Mangrove-swamp peat from top 4 in. in layer ca. 2 ft thick, overlain by marine silt, 1 ft thick (36° 52' S Lat, 174° 40' E Long), N2/185593. Subm. by V. J. Chapman, Auckland Univ. Comment: date places a younger limit on age of formation, which would therefore appear to be no younger than the last interglacial age. 2400 ± 170 NZ-7. Aramaho, Wanganui, North Island 450 B.C. Fossil tree trunk, rooted in place, at bottom of Aramaho pumice quarry, remnant of a forest on flats beside Wanganui River that was buried by floods of pumice alluvium (39° 53' S Lat, 175° 06' E Long), N138/624917. Coll. by C. A. Fleming, N. Z. Geol. Surv. 2420 + 170 NUZ-8. Aramaho, Wanganui, North Island 470 B.C. Charcoal fragments, depth 2 to 5 ft below surface in Aramaho pumice 120 T. L. Grant-Taylor and T. A. Rafter quarry, same locality as NZ-7. Charcoal is believed to have been formed at the time of the pumice eruption and almost immediately brought down to the coast by the Wanganui River. Coll. by C. A. Fleming. Comment: age is similar to NZ-7 and supports the interpretation, but the difference as compared with NZ-1 through NZ-4 (this date list) suggests the possibility of another eruption in the district. NZ-9. Wanganui Valley, Westland, Island 930 ± 150 South A.D.1O2O Wood, buried in gravel deposit that was deformed by late movement of the Alpine fault, Wanganui Valley, 1.25 mi upstream from road bridge (43° 10 S Lat,170 37 E Long). Coll. by C. A. Fleming. NZ-10. Kaingaroa Forest, Rotorua 930 ± 70 A.D. 1020 Wood from 10-in, depth below surface, 3 in. above contact with buried soil developed on Taupo volcanic ash, imbedded in and stratigraphically over- lain by Kaharoa ash, 4 ft thick, and then by Tarawera ash, 6 in. thick, exposed in cut on Northern Boundary Rd., Kaingaroa Forest (38° 19' S Lat, 176° 44' E Long), N86/127801. Coll. by I. L. Baumgart. Comment: sample places an older limit on age of Kaharoa eruption and approximately dates the eruption. NZ-11. Penrose, Auckland 9270 ± 80 7320 B.C. Wood from tree trunk underlying basalt flow, in excavation for overhead bridge on the Penrose main-road deviation (36° 54' S Lat, 174° 49' E Long), N42/330540. Subm. by J. Healy, N. Z. Geol. Surv., Rotorua. Comment: dates one of the younger basalts of the Auckland district. NZ-12. Napier 20,670 ± 300 18,720 B.c. Wood, 5 ft below surface, in deeply weathered pumiceous clay, 9 in. above unweathered pumice and ash, exposed in excavation for Napier Hospital nurses' home, Hospital Hill, Napier (39° 29' S Lat, 176° 54' E Long), N 134/ 317397. Coil, by J. A. Berry, George St., Napier. Comment: sample places a younger limit on deposition of pumice ash and an older limit on deposition of the pumiceous clay, which is loess-like. NZ-13. Rapahoe, Greymouth, Westland 4720 ± 70 2770 s, c. Wood from a large tree trunk, 15 ft above sealevel, imbedded in marine gravel terrace at Rapahoe (42° 23' S Lat, 171° 15' E Long), 544/766972. Coll, by R. P. Suggate, N. Z. Geol. Surv., Christchurch. Comment: terrace ap- parently represents deposition at postglacial sealevel higher than the present one, but tectonic uplift is also probable. NZ-14. Featherston, Wairarapa >37,000 Wood from peat bed, encountered in boring 150 ± 5 ft below sealevel, in an area of postglacial aggradation (41° 13' S Lat, 175° 18' E Long), N161/ 823303. Coll, by I. Barton, Featherston. Comment: sample places a younger limit on peat bed, which is clearly not postglacial. New Zealand Natural Radiocarbon Measurements 1-V 121 840 ± 50 NZ-15. Ohariu Valley,y' Wellingtong ton a.n.1110 Wood from layer of driftwood, overlain by carbonaceous blue clay, 2 ft thick, and then by sandy silt, 8 ft thick, making a depositional river terrace that reaches 12 ft above present stream level (41° 14' S Lat, 174° 44' E Long), N164/294289. Coll, by J. W. Brodie, N. Z. Oceanog. Inst., Wellington. Comment: sequence records local aggradation followed by downcutting; cause of the events is not certainly known. 13,870 ± 250 NZ-16. New Guinea Buna Kokodu area,' 11,920 B.C. Wood from tree trunk imbedded in ash of the earliest phase of volcanic activity in the district (9° 05' S Lat, 148° 09' E Long), Mt. Lamington, an active volcano in the district, has ash deposits that are little consolidated, and is regarded as having begun activity within the last 20,000 yr. Coll. by C. S. Christian, CSIRO, Canberra, Australia. NZ-17. Titahi Bay, Wellington >35,000 Wood from submerged forest, exposed between tide levels, Titahi Bay (41° 06' S Lat, 174° 50' E Long), N160/389441. Bay is backed by a low cliff cut in Pleistocene alluvium; forest bed consists of fossil soil with abundant vegetable remains and stumps in growth position.